Electric switch mechanism



18, 1932- R. A. MILLERMASTER ELECTRIC SWITCH MECHANISM Filed June 5, 1931 3 Sheets-Sheet 1 Filed June 5, 1931 is a 5 5 Sheets-Sheet 3 Patented Oct. 18, 1932 UNITEDv STATES PATENT ori-Ice 1 RALPfi A. MILLERMASTER, OI MITWA'UKEE, WISCONSTN, ASSIGNOR TO CUTLER- HAMMER, INC., 01 MILWAUKEE, WISCONSIN, A CORPORATION OF DELAWARE ELECTRIC SWITCH MECHANISM Application filed June 5,

This invention relates to improvements in electric switch mechanisms, and more particularly to improvements in fused switch devices. v

An object of the invention is to provide an improved switch mechanism together with novel actuating means therefor.

Another object is to provide a novel arrangement of switch and fuse parts to facilitate assembly and wiring thereof within a suitable casing.

Another and more specific object is to eliminate interference by the switch operating means during assembly and wiring of the switch and fuse parts.

Another object is to provide novel means affording access to the fuse receptacle only under given conditions.

Another object is to provide a novel form of interlock between the switch operating means and themeans affording access to the fuse receptacle.

Another object is to provide means operable at will by an authorized person to afford free access to the fuse andswitch parts irrespective of the circuit controlling position of thelatter.

Qther objects and advantages of the invention will hereinafter appear.

The-accompanying drawings illustrate certain embodiments of the invention which will now be described, it being understood that the invention is susceptible of embodiment in other forms without departing from the appended claims.

In the drawings, Figure 1 is a view partly in side elevation and partly in vertical section showing, on a reduced scale, a fused meter service switch constructed in accordance with my invention and mounted within a sheet metal casing of the preferred form.

Fig. 2 is a plan view (normal size) of certain of theswitch and fuse parts shown in Fig. 1.

Fig. 3 is aplan .view showing the main and auxiliary cover members of the metal casing, and the switch operating handle, certain of the other elements of the device being shown in dotted lines.

Serial No. 542,236.

for effecting interlocking engagement between the switch operating means and the auxiliary cover member.

Fig. 6 is a view similar to Fig. 2, but show ing a modified form of fused switching device.

Fig. 7 is a detail perspective view of the modified form of switch actuating element shown in dotted lines in Fig. 6.

Fig. 8 is a sectional view, on the line 88 of Fig.- 6. t

Fig. 9 is a view, partly in section and partly in end elevation, on the broken line 9-9 of Fig. 6.

Fig. 10 is a perspective view, in separated relation, of certain parts of the device illustrated in Figs. 1 to 4, and

Fig. 11 is a bottom plan view of the de-- vice illustrated in Fig. 10.

Referring first to Figs. 1 to 5, 10 and 11 of the drawings, the numeral 15 designates an insulating base which is shaped as shown in the several figures to provide for formation thereof by a straight-line molding operation.

Base 15 is provided on its outer face with a substantially cylindrical hollow projection 16 upon the bottom wall of which a screw shell contact 17 of a fuse receptacle is adapted to rest. The bottom flange of screw shell 17 is provided with a relatively wide diametrical slot (shown in dotted lines at 18, Fig. 2) which likewise extends a short distance up each side of the shell to accommodate the thickness of the terminal element 19, the enlarged head portion 20 of which is adapted to overlie the shell flange.

Upon insertion of terminal 19 into shell 17 these parts may be tilted slightly for inser tion thereof jointly into the recess in projection 16 the downwardly offset end 21 of termi nal 19 passing outwardly through an opening 22 provided in the side wall of said projection by the straight-line molding operation, as shown. End 21 is tapped to receive a binding screw 23,-a testing clip 24 of usual form being clamped in position by the screw head.

Fitted snugly within screw shell 17 is an insulating disk 24 and superimposed thereon is a relatively smaller metal washer 25, said disk and washer having openings to accommodate theshank of a center contact screw 26, and the head 20 of the terminal element 19 is provided with a relatively large perforation 20 to provide clearance for said screw. Screw 26 penetrates base 15 and takes into a tapped opening in a conducting strip or bus member 27 to provide an electrical and mechanical connection therebetween. Member 27 as shown is located in a correspondingly shaped recess 28 in the lower surface of base 15, said member having a portion 29 (Figs.

2 and 10) located in the plane of the main' body thereof but extending at substantially a right angle with respect thereto. The end of portion 29 is bent downwardly (Fig. 2) at a right angle to the plane aforementioned to provide one of the stationary contacts 3001 the switch mechanism. A second screw 31 having its head located in a. countersink 32 penetrates base 15 and takes into a tapped opening in member 27 to assist in holding the latter in position.

The other stationary contact 33 of the switch is located as shown in Fig. 2 in spaced parallelism to the contact 30, said contact 33 being bent upwardly at a right angle to the plane of the conducting strip or bus member 34 which fits snugly within a correspondingly shaped shallow recess in a ledge 35 formed on base 15,-said strip having a tapped opening to receive the shank of a single screw (not shown) which extends 'up'wardly through the base to secure said strip and its integrally formed contact 33 in position. Member 34 is provided with an end portion 34 which is oifset as shown in Fig. 4 to be substantially flush with the offset lower surface 15 of the base,-said end portion 34 being preferably provided with a pair of tapped openings to receive the screws 34*, 34 which are adapted to retain the wireclamping member 34 whereby a terminal connection for one of the line wires is provided; or if desired the ordinary binding connection may be provided by the head of screw 34'.

Slidable between the contacts 30 and 33 is a member 36 formed of black fiber or other suitable tough and relatively rigid insulatmg material, said member being adapted to bear at its lower edge 36 against the relatively narrow portion 35 of ledge 35 as shown in Figs. 2, 4 and 10. The forward end of member 36 is readily insertable into a groove 37 formed in the lower face of base 15,-it being necessary to initially tilt the member 36 downwardly to permit the enlarged end 36 thereof to clear the shouldered projection 37 formed in said slot. Thereafter member- 36 is rectilinearly movable between contacts 30 and 33 and within groove 37, outward movement of said member being limited by engagement of the shouldered end 36 thereof with the inner shoulder of projection 37 and inward movement of said member being limited by engagement of the shoulder 36 (Fig. 2) with the outer shoulder of said projection 37".

Member 36 carries a bridging contactor which preferably comprises a pair of resilient arms 38 and 39 which maybe formed integrally with a cross-piece 40 adapted toseat against the upper edge 36 of member 36. Arms 38 and 39 may therefore be rigidly and permanentlysecured to member 36 as by means of a single rivet 41, eyelet, or similar element. The free end portions of said arms are preferably spaced laterally a slight dist-anEe from the respective sides of member 36, and the tips 38, 39 thereof may be flared apart-as shown to facilitate engagement of said arms with the contacts 30 and 33 (Figs. 2 and 10). The forward edges of said contacts may be beveled as shown to further facilitate such engagement. 'As best indicated in Fig. 4, the arms 38 and 39 are spaced upwardly a short distance above the edge 36 of member 36 to prevent frictional engagement thereof with the portion 35 of the ledge surface 35. Member 36 is also provided with a notch 36 to be engaged by a suitable actuating element, as hereinafter set forth.

Attached to base 15, as by means of the single screw 42 is a wiring terminal strip 43, said strip being positioned within a correspondingly shaped shallow recess in the upper surface of said base. Located beneath strip 43 and clamped in position thereby is a testing clip member 44 of usual form. Strip 43 is provided with wiring terminal screws 45 and 46, the former being adapted for connection with one of the load terminals and one of the meter terminals, and the latter providing for a connection to ground in the usual manner. An otl'set portion 43 of strip 43 is tapped to receive the screws 43, 43, the heads of said screws cooperating with the clamping plate 43 to provide for connection of the other line wire; or if desired the screw 43 may be used alone for that purpose.

Base 15 is provided at the other side there of with a pair of wiring terminal plates 47, 48 which are respectively secured in correspondingly shaped shallow recesses as by means of individual screws 49, 50,the ends of said plates being spaced apart as shown in dotted lines at 51 in Fig. 2, and said plates being normally electrically connected as by means of a strip 52 which is clamped in position by a pair of screws 53, 54. )Vhen it is desired to disconnect plates 47, 48 it is only necessary to unloose screws 53. 54 whereupon strip 52 may he slid backwardly over plate 48 and out of engagement with plate 47, said strip being provided with an elliptical slot 52 and an end notch 52 to permit such move ment. Strip 47 is provided at one end with a tapped opening to accommodate the screw 55 which acts as a'binding connection for one of the terminal wires of a meter (not shown). A test clip 56 may be clamped in position by the screw '55.- Strip 48 is likewise provided at the outer-end thereof with a tapped opening to accommodate the screw 57 which acts as a binding connection for the other load circuit wire (not shown). A test clip 58 may be clamped in position by the screw 57.

Base 15 is supported by an inverted U- shaped bracket 59, said bracket having foot portions 59', 59 which are perforated as shown at 59, 59 for attachment. thereof to the bottom wall 60* of a switch box 60. As shown, the openings 59, 59 are tapped so receive the shanks of screws which extend inwardly through registering openings in said bottom wall. Obviously, however, bracket 59 may be secured within the box 60 in any other suitable manner, as by riveting or spot welding the former to thelatter. As best illustrated in Fig. 4, the bracket 59 acts to assist in guiding and retaining the element 36 within the groove 37, the forward edge of portion 36 being curved as shown to c ear the bracket 59 during insertion or assembly of element 36 within the base groove.

Base 15 is preferably removably secured to bracket 59 as by means of a pair of screws 61, 62 which take into tapped openings in said bracket. Box 60 is preferably of rectangular form as shown, and the upper end wall 60 thereof may be provided with the usual knock-out portions or attachments, not shown, to factilitate connection of the fusedswitch device to a meter.

Box 60 is provided with a main cover 60 which is hinged at 60 to the lower end wall of the box. Cover 60 isprovided with an opening 60 to accommodate the cylindrical projection 16 of the base. Adapted to'overlie the opening 60 is a box-like auxiliary cover member 63, said member 63 having attached thereto a bracket member 64 which is pivotally supported .by a pin 65, the ends of which are flattened and riveted or otherwise secured to the outer surface of cover 60, as shown in Fig. 3. The parallel arms of bracket 64 are provided with arcuate extensions 64*, 64 and cover 60 is provided with slots or openings 64, 64 to provide clearance for said extensions. The arrangement is such that the ends of extensions 64, 64 lie flush with the inner surface of cover 60 when member 63 is in closed position, said extensionswvhen unobstructed. being moved inwardly as member 63 is moved toward its open position see dotted line showing in Fig. 1). The lower end wall 63 of member 63 is provided with a tongue of extension 63*, and cover 60 is provided with an opening 60 to provided clearance for said tongue. Tongue 63' is in turn provided with a slot-or opening 63.

Slidable upon the inner surface of cover 60 is a flat punched sheet metal plate 66 of the form best illustrated in Fig. 5, said plate being supported and guided near one end thereof by a bracket 67 which is riveted, as shown, or otherwise rigidly secured to cover 60. Plate 66 is supported and guided near the other end thereof by a reciprocable handle member 68, the shank 68 of which penetrates an opening in the plate and is slidable between the side and end walls of a slot or opening 69 in cover 60 to have its movements guided and limited thereby. If desired a washer 68 may be interposed between the shoulder 68 of handle 68 and cover 60 to minimize friction between these parts. The reduced inner end 68 of shank 68 penetrates an opening within the flange portion 70 of a switch actuating element 70, said end being upset as shown to rigidly and permanently secure said parts to each other. As best shown in Fig. 5 the flange portion 70 of the actuating element is provided with a spaced 1 pair of extruded bosses or projections 70 which fit within suitable notches on opposite sides of the portion 66 of plate 66, whereby said actuating element is restrained against relative rotary movement.

As shown in Figs. 1 and 2 the actuating element 70 is freely engageable within the notch 36' in member 36 upon closure of cover 60, assuming corresponding positioning ofmember 36 and handle 68. Thus assuming dotted line positioning of the parts 68 and 36 as shown in dotted lines in Fig. 1, it will be understood that the arms 38, 39 of the bridging contactor are disengaged from contacts 30, 33, whereby the fuse parts are entirely disconnected from the line. Also in this position of the parts, the tongue 66 formed on plate 66 will have been withdrawn from the opening 63 in the extension 63 of auxiliary cover member 63, and the portion 66 of the plate will be withdrawn from obstructing relation to the extensions 64, 64 of bracket 64, so that member 63 may be freely swung to its open position to permit access to the fuse receptacle 16. Moreover, the extensions 64, 64 when moved inwardly in the manner aforedescribed are adapted to lie in the path of the portion 66 of plate 66, whereby movement of the latter to effect reclosure of the switch contacts is positively prevented pending reclosure of auxiliary cover member 63.

When member 63 is closed handle 68 may be readily moved upwardly'to efi'ect reclosure of the switch contacts, the tongue 66 of plate 66 at the same time passing through the opening 63 in extension 63 aforcdescribed, and the portion 66 underlying the ends of extensions 64, 64 of bracket 64, whereby auxiliary cover member 63 is positively held in closed position pending 1nove= formed integrally therewith.

ment of handle 68 to its lower extreme position.

Cover 60 is provided with the usual form of latch 71 for retaining the same in closed position, said latch having the usual perforations to provide for attachment of a padlock or seal (not shown) to insure against opening of the main cover 60 by any unauthorized person. However, assuming absence or removal of a padlock 0r seal from the latch 71, it will. be apparent that upon release of saidlatch the cover 60 may be freely opened. to permit full access to the switch and fuse parts irrespective of the circuit controlling position of the switch mechanism.

T have thus far described my invention as embodied in a single phase meter service fused switch for two-wire installations. The device shown in Figs. 6 to 9 is essentially like that aforedescribed, but shows an adaptation of my invention to single phase meter service fused switches for three-wire installations. in this form of the device certain parts are identical in construction and functhe screw shell and center contact elements 17 and 26 of a pair of fuse receptacles. In this case I prefer to have the neck portion 19 and the end portion 21 of each screw shell terminal element located in the plane of the enlarged head portions 18 thereof, re-

' spectively.

Conducting strip 27 is electrically connected with screw 26 for partial support by the latter, theadditional screw 31 being'employed to assist in holding said strip in position within the correspondingly shaped recess in the bottom surface of base 72. Strip Q'Pisformed from a blank identical with that of strip 27, but is bent left-hand as illustrated. Portions 29 and 29 of said strips have the contacts 30 Additional terminal elements 76 areprovided in this form of my invention, said elements being clamped in position by the strips 27, 27 whereby the same are electrically connected with the center contact screws 26. Additional screws 77 are provided to retain elements 7 6 in position,said elements being arranged for electrical connection with the respective ends of the voltage coil of a meter (not shown) as by means of binding screws 76. The other terminal elements of the device are adapted to provide the usual circuit connections between the line, the meter and the load for a three-wire installation.

The bridging contactors and the actuating elements therefor are quite similar to the corres ending parts aforedescribed. In this case have shown each bridging contactor as comprising a pair of separately formed resilient strips 78 and 79, the strips of each pairbeing rigidly secured to opposite sides of an insulating actuating element 80 and electrically connected to each other as by means of a pair of rivets or eyelets 81. The elements 80 are each preferably of the form best illustrated in Fig. 8, wherein the forward end 80 thereof is slidable within a groove 82 in the bottom surface of base 72, a stop shoulder 80 being formed on each element 80 for engagement with a shoulder 82 provided in each groove to limit outward movement of said elements, and each element 80 being also provided with a shoulder 8O engageable with a shoulder on the base to limit inward movement of said elements. The enlarged outer ends 80 of said elements are provided with alined perforations to accommodate a rod or bolt 83, the opposite ends of said rod being threaded and pairs of nuts 84; and 85 being employed to clamp said elements 80 upon the rod in definitely spaced relation to each other.

The switch box (not shown) for a device of this character may be similar to but preferably somewhat larger than that aforedescribed, and the main cover, auxiliary cover, and associated interlocking elements may be of the general character aforedescribed. In this case, however, the operating handle will have attached thereto an operating element 84 of the form illustrated in detail in Fig. 7 and in dotted lines in Fig. 6. As shown element 8 1 is of substantially U-shape and the arms 84 and 84 thereof are provided with notches 84 and 84, respectively; the walls of said notches being adapted to straddle the rod 83 to cause movements of the latter and of elements 80 which correspond with the movements of the operating handle.

Base 72 may be supported by a bracket 86 of inverted U-shape as shown-the flange 87 at each end of the bracket being provided with openings as shown whereby the same may be secured by suitable bolts, screws or the like to the opposite side walls of a box. and in suitably spaced relation to the bottom wall of the latter.

By providing an arrangement of the character herein described whereby the operating element carried by the cover may be readily disconnected from the actuating element or elements of the switch or switches of the device, it will be seen that assemblv, wiring and inspection or repair of the various parts of the device is facilitated. The finished product is neat and attractive in appearance, and the various parts have been so constructed and arranged as to be unlikely to get out of order.

As best shown in- Figs. 1 and 5, the main cover member is provided with an inwardly projecting boss 88 cooperable with opposed edges of portion 66 of member 66 to assist in retaining or latching the latter in its opposite extreme positions.

What I claim as new and desire to secure by Letters Patent is:

1. In a fused switch device, in combination, a box-like sheet metal casing, a main cover member hinged to said casing, a molded insulating base supported within said casing in spaced relation to the rear wall of the latter, a fuse receptacle carried by said base, said-cover member having an opening to'provide access to said fuse receptacle, a switch mechanism comprising a pair of stationary contacts arranged in parellelism in a plane below and to one side of said fuse receptacle, one of said switch contacts being electrically connected to the center contact of the fuse receptacle and the other switch contact being provided with a line terminal, an insulating element slidably engaging the inner surfaces of said contacts and bearing on opposite edges against said insulating base for support thereof by the latter, said insulating element and said base having cooperating shoulders to limit movements of the former with respect to the latter, a bridging contactor comprisin a pair of resilient arms rigidly attached to said insulating element on opposite sides of the latter and electrically connected with each other, said arms having flared end rtions spaced from said insulating mem er and adapted to slidably engage the outer surfaces of said contacts, an operating handle slidably mounted on said cover member and accessible from the exterior of the latter, an element carried by and movable with said handle, and said last mentioned element having a loose interlocking connection with said insulating element to provide for corresponding movements of the latter.

2. In a fused switch device, in combination, a box-like sheet metal casing, a main cover member hinged to said casing, a molded insulating base supported within said casing in spaced relation to the rear wall of the latter, a fuse receptacle carried by said base, said cover member having an opening to provide access to said fuse receptacle, a switch mechanism comprising a pair of stationary contacts arranged in parallelism in a plane below and to one side of said fuse receptacle, one of said switch contacts being electrically connected to the center contact of the fuse receptacle and the other switch contact being provided with a line terminal, an insulating clement slidably engaging the inner surfaces of said contacts and bearing on opposite edges against said insulating base for support thereof by the latter, said insulating element and said base having cooperating shoulders to limit movements of the former with respect to the latter, a bridging contactor comprising a pair of resilient arms rigidly attached to said insulating element on opposite sides of the latter and electrically connected with each other, said arms having-flared end portions spaced from said insulating member and adapted to slidably engage the outer surfaces of said contacts, an operating handle slidably mounted on said cover member and accessible from the exterior of the latter, an element carried by and movable with said handle, said last mentioned element having a loose interlocking connection with said insulating element to provide for corresponding movements of the latter, a hinged auxiliary cover member for said cover opening, and means comprising inter-engaging parts associated with said auxiliary cover member and said operating handle to insure against opening of the former upon switch closing movement of the latter, said parts also acting upon opening of said auxiliary cover member to insure against switch closing movement of said operating handle.

3. In a fused switch device, in combination, a box-like sheet metal casing, a main cover member hinged to said casing, a molded insulating base supported within said casing in spaced relation to the rear wall of the latter, a fuse receptacle carried by said base, said cover member having an opening to provide access to said fuse receptacle, a switch mechanism comprising a pair of stationary contacts arranged in parallelism in a plane below and to one side of said fuse receptacle, one of said switch contacts being electrically connected to the center contact of the fuse receptacle and the other switch contact being provided with a line terminal, an insulating element slidably engaging the inner surfaces of said contacts and bearing on opposite edges against said insulatin base for supportthereof by the latter, said insulating element and said base having cooperating shoulders to limitmovements of the former with respect to the latter, a bridging contactor comprising a pair of resilient arms rigidly attached to said insulating element on opposite sides of the latter and electrically connected with each other, said arms having flared end portions spaced from said insulating member and adapted to slidably engage the outer surfaces of said contacts, an operating handle slidably mounted on said cover member and accessible from the exterior of the latter, an element carried by and movable with said handle, said last mentioned element having a loose interlocking connection with said insulating element to provide for corresponding movements of the latter, a hinged auxiliary cover member for said cover opening, and means comprising interengaging parts associated with said auxiliary cover member and said operating handle to insure against opening of the former upon switch closin movement of the latter, said parts also actmg upon opening of said auxiliary cover member to insure against switch closing movement of said operating handle,

'said main cover member being operable to handle portion exposed upon the outer sur-' face of the latter, said cover havin an open ing therein to provide access to a se receptacle, an auxiliary member hinged to said cover and adapted when closed to" overlie said opening, said auxiliary member having projections at opposite ends thereof and said cover having openings to provide clearance for said projections, said switch actuating element having a part adapted in the switch closing position thereofv to engage one of said projections whereby said auxiliary member is positively held in closed position, and said switch actuating element having an other part adapted in the switch opening posit-ion thereof to be engaged by other of said projections whereby said switch actuating element is restrained against movement pending reclosure of said auxiliary member.

5. In a device of the character described, in combination, a metal casing having-a cover movable to provide access to the interior thereof, a molded-insulating base member supported in said casing, stationary contacts supported by said base in spaced relation to each other, an insulating element supported by said base and movable rectilinearly between said contacts in a plane erpendicular to the cover member and in ad acency to the latter, a bridging contactor carried by said element and adapted for cooperation with said contacts to make or break circuit between the latter, an actuating element carried by said cover and slidably movable with respect thereto, said insulating element having a notch, and said actuating element being engageable with the walls of said notch to effect corresponding movements of the former, said arrangement providing for assembly and wiring of the switch parts within the casing without obstruction by the actuating element thereof.

6. In a device of the character described,- in

combination, a box-like metal casing havinga cover, said cover being hinged to said casing and having means providingfor latching and locking the same 1n closed position, a rectilinearly movable switch actuating element slidably mounted upon the inner surface of said cover and having a handle portion exposed upon the outer surface of the latter, switch and fuse elements mounted within said casing, said cover having an opening to provide access to the fuse elements only, an aux iliary flanged member hinged to said cover and adapted when closed to overlie said fuse elements, projections at opposite ends of said a uxiliary member adapted in opposite extreme positions of the latter to respectively penetrate correspondingly shaped clearance openings in said cover, said actuating element having cooperative engagement with certain of said switch elements, said projections cooperating with said actuating element to permit relatively free movement of the latter to i openand/or closed-circuit position when said auxiliary member is in closed position while insuring against opening of the latter in the closed-circuit position of said actuating element, and certain of said projections also acting to prevent movement of said actuating element to closed-circuit position when said auxiiiary member is in open position.

7. In a device of the character described, in combination, a box-like metal casing having a cover, said cover being hinged to said casing and having means providing for latching and locking the same in closed position, a rectilinearly movable switch actuating element slidably mounted upon the inner surface of said cover and having a handle portion exposed upon the outer surface of the latter, switch and fuse elements mounted within said casing, said cover having an opening to provide access to the fuse elements only, an auxiliary flanged member hinged to said cover and adapted when closed to overlie said fuse elements, projections at opposite ends of said auxiliary member adapted in opposite extreme positions of the latter to respectively penetrate correspondingly shaped clearance openings in said cover, said actuating element'having cooperative engagement with certain of said switch elements, said projections cooperating with said actuating element to permit relatively free movement of the lat ter to openand/or closed-circuit position when said auxiliary member is in closed position while insuring against opening of the latter in the closed-circuit position of said actuating element, certain of said projections also acting to prevent movement of said actuating element to closed-circuit position when said auxiliary member is in open position, and said actuating element being freely dis engageable from the switch elements upon opening of said cover to permit access to the fuse and switch parts irrespective of the circuit controlling position of the latter.

8. In an electric switch, in combination, an insulating slide member having adjacent high and low portions providing a. verticalstop shoulder therebetween, a second vertical stop shoulder formed adjacent to the outer end of said low portion, said high portion having a notch adjacent to .the outer end thereof to freely receive an actuating element, a bridging contact element carried by said insulating member, said contact element comprising resilient arms arran ed on opposite sides of said insulating mem er and having flared ends located adJacent to said firstmentioned stop shoulder, and conducting means penetrating said arms and said insu lating member to rigidly secure said parts to each other. i

9. In an electric switch, in combination, an insulating base having longitudinally spaced upper and lower parallel surfaces and having a vertical opening between the adjacent ends of said surfaces, a pair of substantially rigid stationary contacts secured to said base and arranged in parallelism adjacent to said opening, an insulating member slidably en gaging said parallel surfaces and said contacts to be guided thereby, a bridging contactor comprising a pair of resilient arms rigidly secured to opposite sides of said insulating member and electrically connected with each other, said arms having the free end portions thereof spaced from said insulating member to provide for sliding engagement thereof with the outer surfaces of said sta-' tionary contacts respectively, said base and said insulating member having cooperating shoulders formed thereon to limit movements ofthe latter in opposite directions respectively, and a rectilinearly movable actuating element having cooperative engagement with said insulating member to effect corresponding movement of said bridging contactor.

10. In a fused switch device, in combination, a box-like sheet metal casing, a main cover member hinged to said casing, a molded insulating base supported within said casing, a fuse receptacle carried by said base, said cover member having an opening to provide access to said fuse receptacle only, a switch mechanism for controlling the circuit of said fuse receptacle, said mechanism including a rectilinear-1y movable insulating element the opposite edge portions of which are adapted to bear aga nst said base for support by the latter, said insulating element and said base having cooperating shoulders to limit movements of the former in opposite directions with respect to the latter, an operating handle slidably mounted on said cover member and accessible from the exterior of the latter, an element carried by and movable with said handle, said last mentioned element having a loose interlocking connection with said insulating element to provide for corresponding movements of the latter, a hinged auxiliary cover member for said cover opening, and means comprising inter-engaging parts associated with said auxiliary cover member and said operating handle to iar cover mem insulating base supported within said 0218- 7 ing, a fuse receptacle carried by said base,

said cover member having an opening to provide access to said fuse receptacleonly, a

switch mechanism for controlling the circuit a of said fu'se receptacle, said mechanism including a rectilinearly movable insulating element the opposite edge portions of which are adapted to bear against said base for support by the latter, said insulating element and said base having cooperating shoulders to limit movements of the former in opposite directions with respect to thelatter, an oper ating handle slidably mounted on said cover member and accessible from the exterior of the latter, an element carried by and movable with said handle, said last mentioned element having a loose interlocking connection with said insulating element to provide for corresponding movements of the latter, a

hinged auxiliary cover member for said cover openlng, and means comprising inter-engaging parts associated with said auxlhary cover member and said operating handle to insure against opening of theformerupon switch closing movement of the latter, said parts also acting upon opening of said auxiliary cover member to insure against switch closing movement of said operating handle, said main cover member being operable to effect release of the interlocking connection between said insulating element and the element carried by said handle in any of the respective ositions of said parts to thereby provide i ree access to the parts within said casing.

12. In an electric switch, in combination,

an insulating base adapted to be formed by a straight-line molding operation, said base having longitudinally spaced upper and lower parallel surfaces formed thereon to provide a lateral passage thereinto, and having an opening formed between the adjacent ends of said surfaces, a pair of substantially rigid stationary contacts secured to said base and arranged in parallelism adjacent to said opening, a rectilinearly' movable insulating member slidably engaging said parallel surfaces and said contacts to be guided thereby said insulating member having adjacent high and low ortions providing a vertical stop shoulder t erebetween, a second vertical stop shoulder formed adjacent to the outer end of said low portion, means associated with said high portion to provide an interlocking connection between the same and an actuating element of suitable form, and a contaptor having resilient arms rigidly attached'to said insulating member and movable thereby into and out of bridging relation to said stationary contacts;

13. In an electric switch, 1n combinatlon,

an insulating base adapted to be formed by a straight-line molding operation, said base having longitudinally spaced upper and lower parallel surfaces formed thereon and having an opening formed between the adjacent ends of said surfaces, a pair of substantially rigid stationary contacts secured to said base and arranged in parallelism adjacent to said opening, a rectilinearly movable insulating member slidably engaging said parallel surfaces and said contacts to be guided thereby,

- said base and said insulating member having cooperating shoulders formed thereon to require initial tilting of the latter to elfect engagement thereof with the former, said shoulders thereafter acting to limit movements of said insulating member in opposite directions respectively, a contactor rigidly attached to said insulating member and movable thereby into and out of engagement with said stationary contacts, and an actuating element movable rectilinearly in opposite directions selectively, said actuating element having a releasable interlocking connection with said insulating member.

In witness whereof, I have hereunto subscribed my name.

RALPH A. MILLERMASTER. 

